Alnus rugosa (Du Roi) Sprengel. Speckled Alder. Phen: May-Jun; Jul-Aug. Hab: Swamps, wet thickets, marshes, alluvial shores, other seepy or saturated wetlands. Braided streamhead seepage swamps (in VA). Dist: NL west to SK, south to e. MD, w. VA, WV, IN, n. IL, ne. IA, MN, and e. ND.

Origin/Endemic status: Native

Taxonomy Comments: This taxon has often recently been treated as a subspecies of the European A. incana, but recent studies do not clearly show it as being most closely related to that taxon. A. incana occurs in nc. and ne. Eurasia. A. tenuifolia Nuttall occurs in w. North America, from AK south to CA and NM.

Synonymy ⓘ: = G, W, Hardin (1971a); = Alnus incana (L.) Moench ssp. rugosa (Du Roi) Clausen – FNA3, GrPl, K1, K3, K4, Mi, NE, NY, Pa, Va, Furlow (1990); = Alnus incana (L.) Moench var. americana Regel – C; = Alnus rugosa (Du Roi) Spreng. var. americana (Regel) Fernald – F; = n/a – Tat; < Alnus incana (L.) Moench – Mi; > Alnus incana (L.) Moench – Il; > Alnus rugosa (Du Roi) Spreng. – Il; > Alnus rugosa (Du Roi) Spreng. var. rugosa – F

Links to other floras: = Alnus incana ssp. rugosa - FNA3

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Wetland Indicator Status:

• Atlantic and Gulf Coastal Plain: FACU (name change)
• Eastern Mountains and Piedmont: FACU (name change)
• Great Plains: FACW (name change)
• Midwest: FACW (name change)
• Northcentral & Northeast: FACW (name change)

Heliophily ⓘ: 6